The LH opening screen displays a rather big analog clock in the top right quadrant most of the time. Sometimes it opens with ‘ADEV’ data and no analog clock. What controls what is displayed? 3..

But for this particular project the most important aspect is that every thing on the board is readily available, easy to assemble, flexible for multiple GPS and XO's and shipping a board only in a regular envelop is cheap and so far no problem international.

Building should be as easy as running the makefiles.

But I think what I'll do is go back to the original plan of radiating a pilot tone with some modulation to all channels.. (see pulses3.png)

If it can hold within 1/2 cycle of 60 KHz (10 us) for 47 seconds you can simply sample the top minute sync word. Thats from 59-11 seconds. Always fixed. But thats a bit too easy. NIST gave us a bit more of a challenge. At 10 and 40 past the hour the slow code runs and its format is different.

However, that's normally easy to filter. The receiver adjusts the phase of the time signal once every measurement interval. That means, you'll typically get a phase jump every one second. You can adjust the measurement frequency, 5Hz is certainly possible, maybe more, but consult the data sheet on that. On top, there is the quantization error.

Montana is easy to incorporate and easy to maintain. $70 to incorporate and $15 per year to keep up.

It would be good if the software where easy to modify be most "normal" people. My hope is that if it is easy enough then several people will and they will share their work. The Arduino is very east to program.

WiFi Antenna Easy has simply built a better mouse trap. Most external Wi-Fi antennas plug into a USB port, and that simply does not work. Inevitably, you have conflicts with the laptop's onboard Wi-Fi pick-up system. WiFi Antenna Easy's systems plug into an ethernet port, or, actually, the vast majority of their systems ship with their own router.

The ballpark is several microseconds of noise, but that's on top of your system clock offset. I think it would be easy to see 10 microseconds of offset. You would have to work harder to see smaller numbers. Reminder: Your system may have troubles catching 10 microsecond PPS signals. TAPR says "no longer available" for the FatPPS. I poked John.